Foraging Ivory-billed Woodpeckers in the Singer Tract in Louisiana: matching James T. Tanner´s field notes with his photographs from 1939

Abstract

Few photographs exist of living Ivory-billed Woodpeckers (Campephilus principalis), and no previously known photographs show the species foraging. We found a reference in James T. Tanner’s field notes to several photographs taken on 23 April 1939 of a group of Ivory-billed Woodpeckers foraging in a recently dead pecan tree (Carya illinoinensis). We also found a series of four archived photographs taken by Tanner that shows the same upper branches of a recently dead pecan. We found at least one definitive and probably up to three Ivory-billed Woodpeckers in the photographs, indicating these were the intended subjects. Approximately 30% of the bark is removed from a perch branch between the first and last images in the sequence, consistent with known foraging behavior of Ivory-billed Woodpeckers. The photographs illustrate aspects of Ivory-billed Woodpecker foraging behavior described in the literature and show individuals in the group spaced at distances of <1 m. These are among the last known photographs from the Singer Tract population.